Pre-crash safety (PCS) systems are known; these PCS systems mitigate and/or avoid collision damage between an own vehicle and objects, i.e. obstacles, such as other vehicles, pedestrians, or road structures located in the travelling direction of the own vehicle. Such a PCS system obtains a time to collision (TTC) with an object based on a relative distance of the obstacle with respect to the own vehicle and a relative speed or a relative acceleration of the obstacle relative to the own vehicle. The TTC represents a margin time until which the own vehicle would collide with the obstacle. Then, the PCS system causes a warning device to provide, to the driver of the own vehicle, a warning about the approach of the obstacle, and/or activates a braking device of the own vehicle.
As an example of such a PCS system, there is a vehicle control apparatus disclosed in patent document 1. The vehicle control apparatus disclosed in patent document 1 delays an activation timing of a warning device when the deceleration of the own vehicle is equal to or more than a threshold to correspondingly reduce unnecessary activation of the warning device.